java code comments: // single-line, multi-line / * * /, documentation comments / ** * /

1. Single-line comments //:

// Bank after the end of all the characters will be ignored by the compiler;

2. Multi-line comments / * * /:

All the characters / * and * / are ignored by the compiler

3. Documentation comments / ** * /:

 All characters / * and * / are ignored by the compiler, java unique (used to generate the document);    

My summary: multi-line documentation comments and can not be nested.